Quick connectors are prevalently used, for example, as connectors for connecting fuel tubes of automotive fuel supply systems. A quick connector of this kind including a housing and a retainer is capable of connecting two tubes by simple operations without using any fastening means, such as bolts. The two tubes are connected simply by attaching the housing to one of the tubes, inserting an end part of the other tube in the housing and pressing the retainer into the housing. Representative prior art quick connectors are mentioned in Patent documents 1 and 2.
Referring to FIG. 8, an annular ridge 3 is formed in the outer circumference of an end part of a tube 2 fitted in a housing 4. A slide retainer 5 is pressed radially in a window formed in the housing 4. An end edge 6a of a rib 6 formed in the retainer 5 engages with the annular ridge 3 to retain the end part of the tube 2 in the housing 4.
A compact quick connector disclosed in Patent document 3 has a slide retainer of a thickness far less than that of the retainer 5 shown in FIG. 8, and a housing shorter than the housing 4 shown in FIG. 8.
Patent document 1: U.S. Pat. No. 5,542,716
Patent document 2: JP 2002-206683 A
Patent document 3: U.S. Pat. No. 5,863,077